The International Cessna^® 170 Association

I was just sent an article from Van's AF where they are discussing the damage that an ABC fire ex can do to aluminum and electronics. I had heard that some fire ex are dangerous and am wondering if anyone can verify this concern with the "A" part of ABC. They also claim that BC will not do any damage.
Thx,
Dan

http://www.vansairforce.com/community/s ... hp?t=37475

I think this bulletin will verify it.

http://www.buckeyef.com/Bulletin_abc_dry_chem.asp

use Halon!

At last year's Maintenance Seminar (Branson Convention) a Halon extinguisher was displayed and a short talk was given regarding the different types of extinguishers. Halon is best for aircraft, with CO2 and Bi-carbonate (baking soda) as second choices.

Class "A" fires are common wood, paper, cloth, and some rubber/plastics. (Not of much threat in Cessna 170's.) That is the class of fire that the offensive ammonium phosphates are aimed at, and therefore is a good reason to avoid them around most aircraft.

Class "B" fires are chemical, fuel, oil, etc. and is very well addressed by Halon, CO2, and Bi-carbonate extinguishers.

Class "C' fires are electrical and are very well addressed by Halon, and CO2.

Therefore the BEST extinguishing agents for our type aircraft are Halon. They are expensive, but so are our airplanes and our lives.

CAUTION: Halon isolates and ties-up oxygen and cannot support life in confined areas. As soon as the fire is extinguished (heat and fuel are isolated) move to fresh air, open windows, and/or administer oxygen to humans. CO2 is a liquid which vaporizes and settles and "puddles" in low areas. It will freeze living tissue at close range, therefore should be used judiciously on humans and animals. (Again, Halon shines.) Unconsciousness may occur in confined spaces with both Halon and CO2. Like all extinguishants, Bi-carbonate powder should not be inhaled, but is only temporarily disabling and can be cleaned up by vacuuming and water-wash. Halon and CO2 do not leave residue.